Vapor generator



Sept. 4, 1962 Filed June 28', 1960 3 Sheets-Sheet-l 2/ OL- l--L J d /4/ :l- 2 l i# 1| L- 50 i Uh Z i; A 29 27 3//` l l i i i Z5 j S 4 n M il@ '7 L 2|A i l i?. i i 2 l lff )l i 1 i 1 INVENTOR /mmp A44/v Y ATTO R N EYS sept. 4, i962 H. HANY 3,052,220

VAPOR GENERATOR Filed June 28, 1960 5 Sheets-Sheet 2 INVENTOR /VAWAMD /q/vv ATTORNEYS H. HANY VAPOR GENERATOR sept. 4, 1962 3 Sheets-Sheet 3 Filed June 28, 1960 |"hill ATTORNEYS 3,952,220 VAPR GENERATOR Harald Hany, Kassel-Brasselsberg, Germany, assignor t Henschel-Werke G,m.b.H., Kassel, Germany Filed .lune 2S, 1960, Ser. No. 39,369 Claims priority, application Germany .lune 30, 1959 7 Claims. (Cl. 122-157) This invention relates in general to vapor generators and in particular to a new and useful water tube boiler for steam generation, particularly adapted for train engine heating plants and having straight vertical vapor heating tubes located within the interior o-f a double walled vessel and communicating at their upper ends with an annular liquid chamber.

In water tube boilers which are operated with unprocessed water, great diiiculty is encountered in the accumulation and later removal of scale and of cleaning the tubes of the unit. This is particularly true in clases where the unit itself is very Small because of space requirements. In such units the water frequently spills over and the rate of boiler scale accumulation is increased so that tube cleaning is required at regular short intervals.

In an effort to overcome the diculties mentioned above, it is customary to weld the vapor generating tubes on their upper ends into an annular space and on their lower ends or bottoms into the bottom of an inner portion of the boiler vessel. These tubes forni the main heating surface for evaporation.

The present invention is an improvement over such construction particularly in the arrangement of an interior vessel within an outer vessel and in which the vapor generating tubes connect to an annular liquid chamber at their upper ends and into the space between the two vessels at their lower ends. Liquid is maintained to a level intermediate the height of the annular space above the tubes and extends through the tubes `and through the space between the vessels. With such a construction the evaporation area is increased and drier steam is produced above the liquid level in the annular space.

Since liquid is maintained to a level intermediate the height of the annular space which is above the tops of the tubes, there is less fluctuation lin the demand for make-up liquid during the operation and the tubes are always maintained full of liquid.

The arrangement includes means for directing heating gases downwardly into the interior of the inner vessel and around interconnecting web baille walls between outer tubes thereof and upwardly along the exterior wall of the interior vessel. The vapor generator has a pair of anged portions at the upper periphery of the outer vessel, with an annular packing strip inserted therebetween. The annular liquid chamber is provided with openings to permit easy access to each of the tubes of the boiler for cleaning the tubes and removal of the boiler scale. The liquid circulation of the unit is enhanced by the provision of a downcomer tube located on the :exterior of the outer vessel which interconnects the annular space and the lower portion of the space between the interior and exterior Vessels. Make-up liquid is advantageously directed to the boiler `at the location of the upper connection of the downcomer tube to the annular liquid container.

rates Patent ICC Accordingly, it is an object of this invention to provide an improved vapor generator construction,

A further object of this invention is to provide a vapor generator which includes vertically elongated interior and exterior vessels, one within the other, and an annular liquid reservoir thereabove and including vapor generating tubes interconnecting the interior of the annular reservoir and the lower portion of the space between the interior and exterior vessels.

A further object of the invention is to provide a water tube boiler of high heating effect in which the tubes are easily cleaned and free from boiler scale.

A further object of the invention is to provide an improved boiler construction including a baiiling arrangement for concentric sets of tubes arranged within the interior of a vessel for directing heating gases downwardly in the central portion of the tubes and upwardly around the outside of the bailles along the inner Wall surface of the inner Vessel.

A further object of the invention is to provide a steam boiler including inner and outer vertically elongated vessels and an annular liquid reservoir container at the top thereof, and including vapor generating tubes connecting the annular liquid reservoir at their upper ends and the space between the inner and outer vessels at their lower ends, and including `a downcomer tube on the exterior of the boiler connecting the annular liquid reservoir at its upper end and the space between the inner and outer one of said vessels at its lower end.

A further object of the invention is to provide a vapor generator which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specifica-tion. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a central vertical section through a water tube boiler constructed vin accordance with the invention;

FIG. 2 is a horizontal section taken along the line 2-2 of FIG. 1;

FIG. 3 is a section similar to FIG. 2 but of a boiler including only two sets of concentric vapor generating tube banks;

FIG. 4 is an enlarged fragmentary side elevation of the supply pipe connections; and

FIG. 5 is an enlarged sectional View through the upper annular chamber of a water tube boiler showing detachable covers.

Referring to the drawings in particular, the invention embodied therein includes a vapor generator comprising an outer vessel 1, and an inner Vessel Z. The space between the two vessels is maintained lilled with liquid to be vaporized and the interior wall of the inner vessel forms a heating surface for the liquid. Two concentric banks of vapor generating or heating tubes 4 and 4a in the embodiment of FIGS. l and 2 and one set '4b in the embodiment of FIG. 3 extend upwardly from the space between the bottom 5 of the inner vessel 2 and the bottom 3 of the outer vessel 1 and connect at their upper ends tical tubes 2t) communicate between the upper portion of the space between the interior vessel 2 and the exterior vessel 1 and the annular liquid container 6. yThe water level is maintained as indicated at 21 in the liquid container 6 so that the tubes 4 and 4a or 4b, and the space between the interior and exterior vessels 2 and 1, are maintained full of liquid at all times. The generated vapor is discharged from the generator through conventional rneans, e.g. as shown at 8 with an outlet of the container 6.

Heating gases are directed `downwardly between inner walls 22 of the annular liquid container 6 and they oW into a central portion 24 of the interior vessel 2 at the center of the inner banks of tubes 4 (as indicated by arrow A in FIG. 1). The heating gases thereupon are directed somewhat above they bottom of the inner vessel 2, outwardly (in the direction of arrow B) and around webs or baiiie plates 7 which bridge each of the tubes of the bank as indicated at 4a and 4b (FIGS. 2 and 3, respectively). The baille plates 7 extend from a point spaced from the bottom 5 of the inner vessel 2 and connect at their tops to the bottom of the annular liquid container 6. After clearing the bottom edges of baffle plates 7 (as seen in FIG. 1), the heating gases proceed upwardly between the plates 7 and the inner Wall of vessel 2 until they egress through a flue 27 (see arrow C).

Circulation is enhanced in the device by a downcomer tube 10 which communicates with the annular liquid container 6 at its upper end and the space between the vessels 1 and 2 adjacent the bottom 5 at its lower end. Supply pipes 11 and 12 for make-up liquid are connected to the upper end of the downcomer pipe 10 and flow is regulated by hand operated valves 13 and 14 to direct make-up liquid into the upper portion of the downcomer at the location of its connection to the annular container 6. Short pipes 15 and 16 connect the downcomer 10 to the annular liquid container 6 and the space between the exterior and interior vessels 1 and 2, respectively.

As shown in FIG. l of the drawing, the outer vessel 1 is provided with an upper, outwardly projecting flanged portion 28. This portion supports a mating ange 29 which, by the intermediary of a support member 30, carries the annular liquid container 6. An annular strip 31 or" a suitable packing material may be used between the flanges 28, 29 which are interconnected by conventional means. The short tubes depending fro-m the liquid container 6 provide the communication between the latter and the space between the walls of vessels 1 and 2.

In order to provide for easy cleaning of the heating tubes, a plurality of inspection covers 17 are provided yat spaced locations on a top cover of the annular liquid container 6 (FIG. 5). vThe inspection covers are curved and are maintained in tight engagement on their seats by means of a ilat plate member 18 which is secured by means of nut-and-bolt means 26.

Thus the invention provides a compact boiler which has excellent liquid circulation and is provided with large heating surface areas and improved bate means for directing heating gases iirst downwardly into contact with the Walls of an inner concentric bank of tubes, around the lower ends of baille plates, and thereafter upwardly into contact with the walls of an outer concentric bank of tubes and the interior wall surface of the outer vessel container. Liquid is maintained in an annular heating chamber communicating with the tops of the tubes at a level intermediate the height thereof and downcomer means are provided to circulate liquid exteriorly of the inner vessel outside the heating zone. i

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise without departing vfrom such principles.

What is claimed is:

l. A vapor generator comprising an exterior vessel, an interior vessel within said exterior vessel with the walls thereof spaced from the walls of said exterior vessel and delining therewith a liquid space, an annular liquid container at the top of both of said vessels in communication with said liquid space, at least one substantially concentric row of vapor generating tubes extending with their lower ends into communication with said liquid space and with their upper ends into said liquid container, means for directing heating gases downwardly into said interior vessel and centrally of said rows of tubes, bafe means connecting one of said rows of tubes for directing said heating gases further downwardly at the center of said rows of tubes around one end portio-n of said baille means in a substantially horizontal direction and then upwardly between said baffle means and the side wall of said interior vessel, and flue means for the egress of said heating gases from within said interior vessels.

2. A vapor generator according to claim 1, including downcomer means on said exterior vessel connecting at its upper end said liquid container and at its lower end the lower portion of said liquid space, and supply liquid means connected to said downcomer means for providing make-up liquid.

3. A vapor generator according to claim l, wherein said batiie means comprises an annular web interconnecting said one row of tubes and extending from a point spaced from the bottom of said interior vessel to said liquid container.

4. A vapor generator comprising a vertically elongated exterior vessel, a vertically elongated interior vessel within said exterior vessel with the wall and bottom thereof spaced from the wall and bottom, respectively, of said exterior vessel and defining therewith a liquid chamber, a bank of vapor generating tubes coextensive with both of said vessels and traversing said bottom of the interior vessel, liquid container means connecting the upper ends of said tubes with said liquid chamber, said liquid container means comprising an upper annular portion, flange fmeans on both said exterior vessel and said liquid container in substantially mating engagement with each other, means for directing heating gases downwardly along the interior of said bank of tubes, then around the bottom portion of said directing means in a substantially horizontal direction and thereafter upwardly between said directing means and said wall of the interior vessel, and ilue means for the escape of said heating gases from within said interior vessel.

5. A vapor generator according to claim 4, including a plurality of spaced openings at the top of said annular portion of the liquid container means substantially aligned with the tops of said tubes, said openings being adapted to provide access for cleaning purposes, removable cover means for each of said openings, and tightening means secured to said annular portion for holding a pair of said cover means in vapor-tight engagement with said openings.

6. A vapor generator according to claim 4, wherein said means for directing heating gases comprises a tubular member for guiding said gases downwardly into said interior vessel, and baie plates secured between said vapor generating tubes along their major portion, said plates having a bottom portion spaced above the bottom of said interior vessel for guiding said gases horizontally and then upwardly within the inner wall of said interior Vessel toward said ue means.

7. A vapor generator comprising a vessel for a Vaporiz- -able liquid having a central passage for heating gases,

a bank of vapor generating tubes connecting lower and upper portions of said vessel and traversing said passage, means for introducing liquid into said vessel, baliie means connecting said bank of tubes and extending from their top ends to a location spaced from their bottom ends, means for introducing heating gases through said passage in a substantially `downward direction in continuous contact With said bank of tubes and one side of said bale means, for guiding said gases around the lower end of said bafe means and across lower portions of said tubes below said location, and finally for discharging said gases through said passage in a substantially upward direction in continuous Contact with the other side of said baille means, said vessel comprising means `:forming an annular liquid space completely surrounding said passage, connecting said lower and said upper portions and providing a path for said liquid separated from said bank of tubes by both said baffle means and the outer wall of said passage.

References Cited in the tile of this patent UNITED STATES PATENTS Magee uly 19, Johnson Sept. 10, l)Fleming Jan. 14, Mohn Ian. 30, Watts Sept. 25, Johnson Apr. 30,

FOREIGN PATENTS 

